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# Tag Archives: 3-edge coloring

## Four color theorem: experimenting impasses (as in life)

I still think a solution may be found in Kempe chain color swapping … for maps without F2, F3 and F4 faces (or even without this restriction). Or at least I want to try. How you can solve the impasses … Continue reading

Posted in math
Tagged 3-edge coloring, 4ct, coloring maps, four color problem, Kempe chain, Tait coloring
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## Four color theorem: Cahit spiral chains and Tait coloring

I was experimenting impasses and I found this about spiral chains: Consider all possible maps less than or equal to 18 faces (including the ocean) Do not consider duplicates (isomophic maps) There is still a very large number of possible … Continue reading

Posted in math
Tagged 3-edge coloring, four color theorem, Kempe chain, Tait coloring
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## Four color theorem: 3-edge coloring, impasse and Kempe chain color swapping

It is known that for regular maps, “3-edge coloring” is equivalent to finding a proper “four coloring” of the faces of a map. This post is about coloring impasses, fallacious Kempe chain color swapping (not solving the impasse) and an hypothesis I’d … Continue reading